Posted on 05/18/2016 10:21:45 AM PDT by dayglored
folks who build clocks out of NIXIE tubes.
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Working on one now. Got the tubes from Ukraine. Not cheap either!
No doubt. But the motivation was economic, more than technical. The success of Apple stemmed from the visionary (Jobs) defining requirements that would have takes lots of expensive components to implement (such as a full screen video display) and then Woz (with help from Jobs and others) would turn handstands trying to find ways to implement those features while using as few components (thus cost) as possible. Don Lancaster’s “TV Typewriter 6” did the same thing for the KIM-1, by sharing main memory for video, but it was only a hobbyist toy while the Apple II became pivotal in in “personalizing” the computer.
Sometimes I miss my Commodore 64 (which had a 6502 chip). My first computer; I was a teenager.
I learned BASIC on it, and then taught myself machine code and 6502 assembly language on it. I hand wrote machine code, until I figured out that assemblers would generate the machine code and all I had to do was type in assembling like LDA #255, DEC.
I also studied the internal ROM library, including the floating point math library and figured out how 8-bit processing was able to do multidigit floating point division.
I remember hacking the game “Elite” so that I could be invincible if I wanted.
Goodness. I have some good memories working on those old things. I spent too many hours (every day) programming games on the school’s Trash 80s ...
“Or you can buy an LED clock in a thrift store for $2.”
And if you crack the case of the clock open, throw the contents of it into a pencil case, and take it to school with you, you can get a free trip to the White House and be called things like “budding scientist” if you’re a Mulsim!
I was stationed overseas on what was my last action. Mrs C sent me an Altair kit. Several of my comrades and I got it to work and created a pretty good code machine for that day.
It was an Intel 8080 chip set. Had to leave it with the embassy.
Back state side I built a SWTP 6800 and realized how much more superior the motorola/mosfet cpu’s were to the intel ones. I memorized the instruction set of both the 8080 and the 6800, can still program the motorola controller chips raw without a high level language.
Just saying
Caddis the Elder
Cool! I also remember the Altair 8800. We had one in school back in 1977 or 1978 as I recall.
In about the same time frame, I also remember going somewhere where someone did a talk about that new-fangled fiber optic technology.
I worked at Datapoint in my first job out of school. They pioneered in a lot of areas, including the first token ring LAN. They sold that technology to Novell and it became netware. Datapoint developed the first desktop computers and the CPU was built using discrete components with minimal integrated circuits. They sold that technology to Intel and it became the 8008. The 8008 was the first 8 bit microprocessor.
The good old days.
When I was a teenager, I built a transmitter out of a bunch of parts I had about. It even worked rather than going up in a puff of smoke, but the President never called and there were no glowing editorials about how I was the smartest person since Einstein, lol.
About 3 million TI-99/4A computers were sold. The C-64 (based on the 6502, but with 6 extra I/O pins) sold around 17 million units (best selling computer model of all time). The VIC-20 did about another 3 million on that.
The 6502 really was the dominant processor of the time. The Z-80 was around, but was outsold about 6 to 1 by the 6502 cores.
That thing gives me flashbacks to my days as a student learning electronics. Breadboard and wire-tie nightmares that 30-odd years later have only recently begun to subside.
Thanks a lot...
Wan’t the Z-80 used in microwaves and other appliance for years?
Still have an Osborne stuck in the closet.
There is one thing Jobs excelled at, though - taking credit for everything.
I loved the 6502!
Most fun I ever had coding in assembler.
I am a piker compared to Wozniak, his code for the Apple floppy disk controller is epic. He eliminated virtually all the hardware needed for the interface...saved $$$
“When I was a teenager, I built a transmitter out of a bunch of parts I had about.”
Exactly! Back in the late 80s when I was a lunatic young teen, I built a binary counter using one of those Heathkit type of kits. A teacher in high school saw that I had quite an interest in computers and figured he’d get me hooked on digital electronics (which he did, and I can’t thank him enough for it as prior to that I called electronics “scary” ... I had major confidence issues)
When I first powered it up, it did nothing though one chip got really hot! Just as I was about to call it a digital heater, the power supply tripped. Turns out I soldered components on the wrong side of the board :-). I mean, it made sense to solder the components so that you could see the entire silkscreen :-). There were directions I could have followed, but those are for rank amateurs and people that like to get things right the first time :-).
I got another kit and it worked great!
That scumbag Reagan never called me up for a trip to the White House :-) .
I got a huge pile of Burroughs 5031 Nixies in a pile of junk I bot. The junk I waned and bot is worth almost nothing, I hope to get my cost out of the Nixies!
Apparently it is hard as hell to find those 7442 HV driver chips.
Now the ‘scope clocks......I kind of like those. You just have to have a high voltage shock hazard thing going all the time.
I love projects like that but they are so bloody time consuming, even if you have good electronics/soldering chops. Daunting. Challenging as to attention span. Even with my screen name.
My first KIM was like the photo you posted, early release with white ceramic 40-pin chips. I had to leave that one behind when I moved in 1978 (details unimportant) and so I ended up replacing it with one that had the black epoxy chips, which wasn't quite as cool looking but worked just as well.
I piggy-backed a second set of 1Kbitx1 2102 SRAM chips over the existing set... Wow, a whole 2KB of RAM!!
Around 1979 I found a bunch of surplus bare PCBs about 4"x6" that each could hold quantity 32 of the 2102s. So each board could hold 4KB -- a VAST amount compared to the KIM's 1KB... And I scrounged enough 2102s to populate seven of those boards, so I had 28KB of RAM. Every chip hand-soldered, every pin... The boards were stacked and cross-wired into a 3D matrix that looked vaguely reminiscent of a 7-layer 3D chess board. Wirewrapped some address selectors and bus buffers, and the KIM drove it just fine.
*sigh*
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